1. Field of the Invention
This invention relates to a semiconductor device. For example, it relates to a USB memory device with a copyright protection function.
2. Description of the Related Art
Recently, a universal serial bus (USB) memory using a flash memory has been widely utilized as a removable recording medium for use in a personal computer (PC).
The USB memory device, however, has no mechanism for protecting the copyright of content recorded in the USB memory device and it cannot record the content which requires copyright protection, or even if it can, the content cannot be reproduced in a PC and the like.
Jpn. Pat. Appln. KOKAI Publication No. 2003-317054 discloses a memory having a USB interface and a secure digital (SD™) interface, which can be switched between a USB function and an SD™ function. However, when using the USB function, the SD™ function is not available.